What rear springs? 1966 Skylark sportcoupe w/71 8.5 rearend

I've got a 66 Skylark sport coupe with a 71 8.5 rear-end and a 455. Stock suspension(no drop). What springs do I need for the rear? Any one got any part numbers?

Thanks.

 

I use 6197 on my '66's. It's the HD spring so it's a bit higher than stock, but barely. Works well with a larger 15 inch tire like a 255/60 or 275/60.

 

Here's my red '66 with 6197 on rear, 6033 in front.
Tires are 255/60-15 rear, 235/60-15 in front.

 

Very nice! Does it have an 8.5 rear in it? And if not, would the springs you recommended make my car sit different because of it?

 

I'm using Global West S-61's in my '64 with a 1970 12 bolt rear.

 

It has the stock 8.2 rear.
Both the 64-66 and 67-72 springs have the pigtail end of the spring sitting on the rear axle.
The 66 rear spring seat is same height as the top of the axle tube. I don't think there is a height difference on the later rears.